Please remove wesnoth-1.13 from unstable. This package is not suitable
for release, since it's the development branch of wesnoth;
wesnoth-1.12 is the current stable branch that is suitable to be
included in a stable release. We intend to maintain development
branches of wesnoth in experimental only from now on. Thanks!
(rhonda, if you have any additional rationale to add, please feel free to do so)